Removing defunct OpenMAX code (round 2).

All of this code hasn't been used in over a year and has been replaced by VideoDecodeAccelerator and it's corresponding OpenMAX implementation OmxVideoDecodeAccelerator.

BUG=none
TEST=the world still compiles

Review URL: http://codereview.chromium.org/7066071

git-svn-id: http://src.chromium.org/svn/trunk/src/build@90697 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

all.gyp

@@ -553,7 +553,6 @@
             '../jingle/jingle.gyp:jingle_unittests',
             '../media/media.gyp:ffmpeg_tests',
             '../media/media.gyp:media_unittests',
-            '../media/media.gyp:omx_test',
             '../net/net.gyp:net_unittests',
             '../printing/printing.gyp:printing_unittests',
             '../remoting/remoting.gyp:remoting_unittests',